process.nextTick(function() {
    console.log('nextTick callback !')
})

console.log('nextTick was set !')
console.info(__filename)
console.info(__dirname)

process.on('exit', (code) => {
    console.log('about to exit with code: ' + code)
})

/**
 * 浏览器中的全局变量是 widnow 唯一的全局变量
 * 
 * nodejs 中的全局变量 global 唯一的全局变量
 * 
 * global.process 或者 process 是描述 nodejs 进程的
 *  当程序退出时
 *  process.on('exit', () => {
 *      console.log('node exit')
 *  })
 * 
 */